This invention relates to inline check valves and more particularly to an inline check valve positioned within an enlarged diameter valve chamber for directing fluid flow between axially aligned inlet and outlet flow passages with a minimum of turbulence.
Heretofore, inline check valves have been provided within an enlarged valve body in axial alignment with aligned inlet and outlet flow passages of the valve body. Normally a piston check valve member is mounted within the valve body for movement between seated closed position and an unseated open position with resilient spring means urging the piston check valve member to seated closed position. The piston check valve member is usually removable from the valve chamber upon removal of the annular seat about the inlet flow passage but the supporting structure, such as a cage, has normally not been removable from the inlet flow passage since the cage has been of a larger diameter.
Further, the supporting cage structure heretofore has included support ribs which extend radially outwardly from the check valve member into the valve chamber and into the normal flow stream through the valve. Such a radial projection of the ribs thus restricts normal fluid flow through the valve and oftentimes creates a turbulence in the flow stream. Normally the ribs are supported laterally by the valve body and the cage structure for the ribs oftentimes has a complex shape which is relatively difficult and costly to manufacture. Such an arrangement requires a relatively large valve chamber for receiving the ribs and supporting cage structure, and the smooth fluid flow between the inlet and outlet flow passages is interrupted by the cage structure to provide turbulence. In addition, the cage by having ribs extending radially beyond the piston valve member cannot be removed from the valve chamber upon removal of the inlet valve seat such as might be desirable for assembly of the valve or for repair.